The Ambassador Bridge connecting Windsor, Ont., and Detroit, Mich., carries one quarter of all trade between Canada and the United States.

It could soon be carrying hazardous materials, too.

Michigan transportation officials want state lawmakers to allow hazardous materials to cross North America's busiest commercial land border crossing. According to the Michigan Department of Transportation, 1,200 loads of hazardous materials cross between Canada and the U.S. in southern Ontario every day.

Officials now want gases, flammable liquid, peroxides, poisonous and corrosive materials to be allowed to cross the span while being escorted.

'Our whole economy is at risk.'— Greg Ward, ferry owner

Currently, potentially dangerous goods cross the Detroit River on a ferry owned by the Canadian Maritime Transport Limited headed by Greg Ward, from Windsor.

For 23 years, the ferry has carried flammable and corrosive materials, such as paint, alcohol, gasoline, diesel fuel and corrosives used in the automotive industry. The ferry runs between Brighton Beach in west Windsor and the heavily industrialized Zug Island in Michigan.

Ward is against any changes to the current laws.

"It's an 80-year-old-plus structure and if something happens to it, our whole economy's at risk," he said.

Right now, dangerous goods cross the Detroit River on a ferry. (CBC News)

Ward does admit that he has a financial stake in the argument. He said the bridge would have "a monopoly" on hazardous goods and that he "wouldn't be in business."

People on both sides of the border are concerned about allowing hazardous materials on the Ambassador Bridge.

"There are numerous things that can happen. You could have an explosion, you could have leakage going into the river, and there's no way of containing those things," said Windsor councillor Ron Jones. "My feeling is that we could be putting a good amount of people at risk."

According to the Ambassador Bridge website, 7,400 commercial vehicles cross the bridge every day. According to the U.S. Bureau of Transportation Statistics, more than 11,000 passenger vehicles crossed the span on average each day in 2012.

Fire chief questions idea

Windsor's fire chief said the 83-year-old, four-lane bridge doesn't have what it takes to deal with a major accident. There is no easy access for emergency responders and no easy way to get vehicles off the bridge, Bruce Montone said. He also pointed out that there is no water supply on the bridge.

"This is a bridge that was built many, many years ago. Times have changed," Montone said. "If this is going to be permitted, we need to consider what additional measures we need to put in place.Our capacity to deal with those kinds of incidents on the bridge is greatly reduced.

"We have an ability on the ground to deal with access, to deal with crowd control and protecting the residents and to deal with containment issues."

The Ambassador Bridge is privately owned by billionaire Matty Moroun.

Ambassador Bridge company president Dan Stamper said special precautions, including hiring its own first responders. Stamper said the barge puts people at risk.

"Today, the traffic's going through the community to get to the barge and it's going through the community in Windsor to get away from the barge," Stamper said. "We're going to do this with emergency services, vendors, along with our guys being trained as first responders. We're going to have the facilities to hold them if there's a problem and so I don't see this as any risk."

Radioactive material banned

Stamper and the Michigan Department of Transportation both said some goods, such as radioactive materials, would not be allowed to cross.

Thursday at a public meeting in Detroit, residents and politicians spoke out against the proposed changes.

"The worry for me is that 27 per cent of trade comes across that bridge every single day," said Rashida Tlaib, a Democrat in the State House of Representatives. "That trade is so essential and so important and now to mix it with the hazmat material waste to come across with it jeopardizes that trade."

She said the truck ferry is the best option still available.

"Both the Windsor and Detroit folks and Homeland Security have been trained in dealing with any kind of spills or disaster because of that transportation," she said. "But I don't think that's been done here with the Ambassador Bridge Company."

The Michigan Department of Transportation is confident the bridge is a safe crossing.

"We went through a technical analysis that really looked at the risks associated with different types of hazardous materials, the risk to the infrastructure itself, as well as to the public," said Tony Kratofil, a spokesman for the department.

'The bridge is inherently most vulnerable to explosive materials.'— Michigan Department of Transportation

According to a report, the department says, "the bridge is inherently most vulnerable to explosive materials. As a result of limited escape paths, in the event of a hazmat incident resulting in an explosive-caused fire or a toxic release triggered by an explosion, many vehicle occupants might be trapped and possibly not survive."

The department is recommending Class 1 materials, or "explosives," not be allowed to cross.

The report also said toxic releases "pose a less significant concern because these releases would be elevated."

The department recommends that gases, flammable liquid, peroxides, poisonous and corrosive materials be allowed to cross the span while being escorted.

City of Windsor concerned

Michigan's proposed changes only affect roads leading up to the bridge and the span itself. Canadian laws govern the plaza on the Canadian side of the border and the Ontario roads leading to and from the bridge.

That means approval in Michigan doesn't mean approval on the Canadian side. The City of Windsor plans to fight the proposed changes.

However, according to Transport Canada, the Transportation of Dangerous Goods Act does not restrict dangerous goods, known as hazardous materials in the U.S., from Canadian roadways. It only regulates the safe transportation of the materials. For example, proper signage on trucks hauling the goods is required.

Also, the International Bridges and Tunnels Act does not preclude dangerous goods from being on the bridge.

City engineer Mario Sonego said council will make a submission outlining its concerns to the Michigan Department of Transportation.